Full-Scale Bridge Finite-Element Model Calibration Using Measured Frequency-Response Functions

A frequency-response function–based parameter-estimation method was used for finite-element (FE) model calibration of a fullscale bridge using measured dynamic test data. Dynamic tests were performed on the bridge to obtain measured frequency-response functions. Data quality was ensured by comparing measured data with the FE model and removing erroneous data. A coherence data selector was developed to remove the noise-contaminated portions of themeasured frequency-response functions. An unrefined FEmodel was created using design information for the geometry and structural parameters. This model was improved to a refinedmodel by using concrete cylinder property data, as-built drawing geometry, and the addition of components that participate in the dynamic response of the bridge. Simulations were performed using the model to ensure both observability and identifiability of structural parameters. The model of the bridge was then calibrated successfully usingmeasured frequency-response functions. An increase in the negative bending region concrete-deck rigidity was found during the calibration and verified by increased reinforcement in that area. Examining the second norm of the residual between the different models and the measured data resulted in an improvement from the unrefined to the calibrated FE model. The proposed method proved to be robust in the presence of modeling andmeasurement errors and computationally efficient for use with full-scale structures.DOI:10.1061/(ASCE)BE.19435592.0000705. © 2014 American Society of Civil Engineers. Author keywords: Frequency-response function; Parameter estimation of structures; Finite-element (FE) model calibration; Optimization; Full-scale bridge; Dynamic testing.